Mobility aids including crutches of various designs have long been used to assist people with injuries or other temporary or permanent disabilities. In order to accommodate users having diverse body dimensions, typical commercially available crutches are adjustable in overall height and in the position of a handle along the overall height. A typical commercially produced crutch has body components made of wood (see, e.g., U.S. Pat. No. 815,368) or aluminum (see, e.g., U.S. Pat. No. 4,838,291). Such body components typically have multiple holes by which they can connect to one another using metal bolts and metal wing nuts. Depending on the particular holes selected for use, overall height and handle position is determined. Typically, there is only one adjustment point for the overall height.
Despite their long history of existence, conventional crutches have problems of being uncomfortable to use due to their rigidity, expensive to produce due to their complexity, and expensive to produce and keep as inventory due to a need for multiple sizes of crutches caused by the limited height adjustability of any one crutch. Another problem is that metal components used in crutches tend to trigger metal detector alarms, for example, at airports.